Bio-medical

The use of analysis and simulation for bio-medical purposes is
increasing dramatically but is still quite immature. In contrast to
other industrial sectors most analysis work is carried out by
“specialists” in consultancies, universities or
research establishments and industrial “practises” are
in there infancy. Nevertheless the potential benefits are
substantial.

There are two distinct drivers; firstly an improved understanding
of the biomechanics of human body with view to development of
artificial implants, e.g. hip replacements, artificial heart
valves. Secondly the simulation of body kinematics in crash
scenarios in response to the need for safer cars, trains etc.

In the first case the use of CAE techniques gives insight into the
load mechanisms, material behaviour and response of the implants
and the biomedical materials (bone, cartilage, ligaments, muscles,
etc.). They can support the product design and development process
in many aspects, such as wear predictions, structural behaviour,
component loading etc. In the second area the interest is
understanding how the human body interacts in crash situations when
subject to very rapid decelerations, with a view to designing safer
vehicles.

The main challenge in both areas is how to tackle the highly
nonlinear and currently illunderstood biomechanical behaviour of
specific materials using the available simulation tools. Much of
the “material” behaviour is not easily characterised by
conventional models e.g. “solids” usually behave in a
complex inelastic manner and fluids are non-Newtonian.

Other technology challenges include a general lack of credible
data, ill-understood scale effects and the ability of material to
change behaviour in response to environment. It is thus essential
to bring together the specialist bio-medical knowledge and the
expertise and experience of finite element analysis specialists, in
order to adapt the already existing advanced finite element
formulations and techniques on the special biomechanical
requirements.

An additional group of problems stems from the ever increasing use
of micromechanisms and microsystems in medical applications.
Typical devices include microfluidic, electrical and sensing
components. Problems associated with design and use of these
devices requires solution to coupled physics issues such as; flow,
heat transfer, chemistry and diffusion or structural analysis,
electrostatics, electromagnetics and plasma.

Advanced tools are emerging. However the computing power required
is demanding and there is considerable scope for research directed
at better models.